Metallic sealing rings are known in installations encountering high pressure or high temperature, or both, including axial pressure type installations in which the sealing ring surrounds a fixed rod, shaft or like projection. Frequently the sealing ring exterior is coated with another, softer material for example silver. The flow of the finish material improves sealing.
In installing the sealing ring it has been conventional to place the ring under compression to occasion a springback effect in which opposing surfaces on the seal are urged outward into contact with surfaces to be sealed. In an axial pressure type installation, this compression has been obtained by forming a taper or bevel on either one or both parts contacted by the seal, so that, in the course of inserting the seal in its accommodating recess, it will inherently be compressed a proper amount in a radial sense. One objection to this procedure is that the added machining in forming the taper or bevel represents added cost. Another objection is that in sliding the seal in place against frictional resistance, sealing surfaces thereon may be scratched or otherwise damaged. Imperfect sealing can result and the seal may be made unfit for repeated use. In addition, repeatability of an accomplished seal may be difficult to achieve with replacement seals which are dimensioned at extremes of an allowable range of tolerances. In the drawings hereof, and in description to follow, a prior art seal installation is disclosed. That disclosure, taken with the foregoing statement of the background of the invention, constitutes the state of the art, prior to this invention, as applicant and those associated with him in preparation of this application for patent are aware of it.